* and join trees.
*
*
- * Portions Copyright (c) 1996-2014, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/nodes/primnodes.h
#define PRIMNODES_H
#include "access/attnum.h"
+#include "nodes/bitmapset.h"
#include "nodes/pg_list.h"
*
* Note: colnames is a list of Value nodes (always strings). In Alias structs
* associated with RTEs, there may be entries corresponding to dropped
- * columns; these are normally empty strings (""). See parsenodes.h for info.
+ * columns; these are normally empty strings (""). See parsenodes.h for info.
*/
typedef struct Alias
{
List *colnames; /* optional list of column aliases */
} Alias;
-typedef enum InhOption
-{
- INH_NO, /* Do NOT scan child tables */
- INH_YES, /* DO scan child tables */
- INH_DEFAULT /* Use current SQL_inheritance option */
-} InhOption;
-
/* What to do at commit time for temporary relations */
typedef enum OnCommitAction
{
* RangeVar - range variable, used in FROM clauses
*
* Also used to represent table names in utility statements; there, the alias
- * field is not used, and inhOpt shows whether to apply the operation
+ * field is not used, and inh tells whether to apply the operation
* recursively to child tables. In some contexts it is also useful to carry
* a TEMP table indication here.
*/
char *catalogname; /* the catalog (database) name, or NULL */
char *schemaname; /* the schema name, or NULL */
char *relname; /* the relation/sequence name */
- InhOption inhOpt; /* expand rel by inheritance? recursively act
+ bool inh; /* expand rel by inheritance? recursively act
* on children? */
char relpersistence; /* see RELPERSISTENCE_* in pg_class.h */
Alias *alias; /* table alias & optional column aliases */
int location; /* token location, or -1 if unknown */
} RangeVar;
+/*
+ * TableFunc - node for a table function, such as XMLTABLE.
+ */
+typedef struct TableFunc
+{
+ NodeTag type;
+ List *ns_uris; /* list of namespace uri */
+ List *ns_names; /* list of namespace names */
+ Node *docexpr; /* input document expression */
+ Node *rowexpr; /* row filter expression */
+ List *colnames; /* column names (list of String) */
+ List *coltypes; /* OID list of column type OIDs */
+ List *coltypmods; /* integer list of column typmods */
+ List *colcollations; /* OID list of column collation OIDs */
+ List *colexprs; /* list of column filter expressions */
+ List *coldefexprs; /* list of column default expressions */
+ Bitmapset *notnulls; /* nullability flag for each output column */
+ int ordinalitycol; /* counts from 0; -1 if none specified */
+ int location; /* token location, or -1 if unknown */
+} TableFunc;
+
/*
* IntoClause - target information for SELECT INTO, CREATE TABLE AS, and
* CREATE MATERIALIZED VIEW
* upper-level plan nodes are reassigned to point to the outputs of their
* subplans; for example, in a join node varno becomes INNER_VAR or OUTER_VAR
* and varattno becomes the index of the proper element of that subplan's
- * target list. But varnoold/varoattno continue to hold the original values.
- * The code doesn't really need varnoold/varoattno, but they are very useful
- * for debugging and interpreting completed plans, so we keep them around.
+ * target list. Similarly, INDEX_VAR is used to identify Vars that reference
+ * an index column rather than a heap column. (In ForeignScan and CustomScan
+ * plan nodes, INDEX_VAR is abused to signify references to columns of a
+ * custom scan tuple type.) In all these cases, varnoold/varoattno hold the
+ * original values. The code doesn't really need varnoold/varoattno, but they
+ * are very useful for debugging and interpreting completed plans, so we keep
+ * them around.
*/
-#define INNER_VAR 65000 /* reference to inner subplan */
-#define OUTER_VAR 65001 /* reference to outer subplan */
-#define INDEX_VAR 65002 /* reference to index column */
+#define INNER_VAR 65000 /* reference to inner subplan */
+#define OUTER_VAR 65001 /* reference to outer subplan */
+#define INDEX_VAR 65002 /* reference to index column */
#define IS_SPECIAL_VARNO(varno) ((varno) >= INNER_VAR)
Index varno; /* index of this var's relation in the range
* table, or INNER_VAR/OUTER_VAR/INDEX_VAR */
AttrNumber varattno; /* attribute number of this var, or zero for
- * all */
+ * all attrs ("whole-row Var") */
Oid vartype; /* pg_type OID for the type of this var */
int32 vartypmod; /* pg_attribute typmod value */
Oid varcollid; /* OID of collation, or InvalidOid if none */
/*
* Const
+ *
+ * Note: for varlena data types, we make a rule that a Const node's value
+ * must be in non-extended form (4-byte header, no compression or external
+ * references). This ensures that the Const node is self-contained and makes
+ * it more likely that equal() will see logically identical values as equal.
*/
typedef struct Const
{
int location; /* token location, or -1 if unknown */
} Const;
-/* ----------------
+/*
* Param
- * paramkind - specifies the kind of parameter. The possible values
+ *
+ * paramkind specifies the kind of parameter. The possible values
* for this field are:
*
* PARAM_EXTERN: The parameter value is supplied from outside the plan.
* `paramid' field. (This type of Param is converted to
* PARAM_EXEC during planning.)
*
- * Note: currently, paramtypmod is valid for PARAM_SUBLINK Params, and for
- * PARAM_EXEC Params generated from them; it is always -1 for PARAM_EXTERN
- * params, since the APIs that supply values for such parameters don't carry
- * any typmod info.
- * ----------------
+ * PARAM_MULTIEXPR: Like PARAM_SUBLINK, the parameter represents an
+ * output column of a SubLink node's sub-select, but here, the
+ * SubLink is always a MULTIEXPR SubLink. The high-order 16 bits
+ * of the `paramid' field contain the SubLink's subLinkId, and
+ * the low-order 16 bits contain the column number. (This type
+ * of Param is also converted to PARAM_EXEC during planning.)
*/
typedef enum ParamKind
{
PARAM_EXTERN,
PARAM_EXEC,
- PARAM_SUBLINK
+ PARAM_SUBLINK,
+ PARAM_MULTIEXPR
} ParamKind;
typedef struct Param
* ressortgroupref indexes to let them be referenced by SortGroupClause
* entries in the aggorder and/or aggdistinct lists. This represents ORDER BY
* and DISTINCT operations to be applied to the aggregate input rows before
- * they are passed to the transition function. The grammar only allows a
+ * they are passed to the transition function. The grammar only allows a
* simple "DISTINCT" specifier for the arguments, but we use the full
* query-level representation to allow more code sharing.
*
* DISTINCT is not supported in this case, so aggdistinct will be NIL.
* The direct arguments appear in aggdirectargs (as a list of plain
* expressions, not TargetEntry nodes).
+ *
+ * aggtranstype is the data type of the state transition values for this
+ * aggregate (resolved to an actual type, if agg's transtype is polymorphic).
+ * This is determined during planning and is InvalidOid before that.
+ *
+ * aggargtypes is an OID list of the data types of the direct and regular
+ * arguments. Normally it's redundant with the aggdirectargs and args lists,
+ * but in a combining aggregate, it's not because the args list has been
+ * replaced with a single argument representing the partial-aggregate
+ * transition values.
+ *
+ * aggsplit indicates the expected partial-aggregation mode for the Aggref's
+ * parent plan node. It's always set to AGGSPLIT_SIMPLE in the parser, but
+ * the planner might change it to something else. We use this mainly as
+ * a crosscheck that the Aggrefs match the plan; but note that when aggsplit
+ * indicates a non-final mode, aggtype reflects the transition data type
+ * not the SQL-level output type of the aggregate.
*/
typedef struct Aggref
{
Oid aggtype; /* type Oid of result of the aggregate */
Oid aggcollid; /* OID of collation of result */
Oid inputcollid; /* OID of collation that function should use */
+ Oid aggtranstype; /* type Oid of aggregate's transition value */
+ List *aggargtypes; /* type Oids of direct and aggregated args */
List *aggdirectargs; /* direct arguments, if an ordered-set agg */
List *args; /* aggregated arguments and sort expressions */
List *aggorder; /* ORDER BY (list of SortGroupClause) */
List *aggdistinct; /* DISTINCT (list of SortGroupClause) */
Expr *aggfilter; /* FILTER expression, if any */
bool aggstar; /* TRUE if argument list was really '*' */
- bool aggvariadic; /* TRUE if VARIADIC was used in call */
+ bool aggvariadic; /* true if variadic arguments have been
+ * combined into an array last argument */
char aggkind; /* aggregate kind (see pg_aggregate.h) */
Index agglevelsup; /* > 0 if agg belongs to outer query */
+ AggSplit aggsplit; /* expected agg-splitting mode of parent Agg */
int location; /* token location, or -1 if unknown */
} Aggref;
+/*
+ * GroupingFunc
+ *
+ * A GroupingFunc is a GROUPING(...) expression, which behaves in many ways
+ * like an aggregate function (e.g. it "belongs" to a specific query level,
+ * which might not be the one immediately containing it), but also differs in
+ * an important respect: it never evaluates its arguments, they merely
+ * designate expressions from the GROUP BY clause of the query level to which
+ * it belongs.
+ *
+ * The spec defines the evaluation of GROUPING() purely by syntactic
+ * replacement, but we make it a real expression for optimization purposes so
+ * that one Agg node can handle multiple grouping sets at once. Evaluating the
+ * result only needs the column positions to check against the grouping set
+ * being projected. However, for EXPLAIN to produce meaningful output, we have
+ * to keep the original expressions around, since expression deparse does not
+ * give us any feasible way to get at the GROUP BY clause.
+ *
+ * Also, we treat two GroupingFunc nodes as equal if they have equal arguments
+ * lists and agglevelsup, without comparing the refs and cols annotations.
+ *
+ * In raw parse output we have only the args list; parse analysis fills in the
+ * refs list, and the planner fills in the cols list.
+ */
+typedef struct GroupingFunc
+{
+ Expr xpr;
+ List *args; /* arguments, not evaluated but kept for
+ * benefit of EXPLAIN etc. */
+ List *refs; /* ressortgrouprefs of arguments */
+ List *cols; /* actual column positions set by planner */
+ Index agglevelsup; /* same as Aggref.agglevelsup */
+ int location; /* token location */
+} GroupingFunc;
+
/*
* WindowFunc
*/
* entire new modified array value.
*
* If reflowerindexpr = NIL, then we are fetching or storing a single array
- * element at the subscripts given by refupperindexpr. Otherwise we are
+ * element at the subscripts given by refupperindexpr. Otherwise we are
* fetching or storing an array slice, that is a rectangular subarray
* with lower and upper bounds given by the index expressions.
* reflowerindexpr must be the same length as refupperindexpr when it
* is not NIL.
*
+ * In the slice case, individual expressions in the subscript lists can be
+ * NULL, meaning "substitute the array's current lower or upper bound".
+ *
* Note: the result datatype is the element type when fetching a single
* element; but it is the array type when doing subarray fetch or either
* type of store.
+ *
+ * Note: for the cases where an array is returned, if refexpr yields a R/W
+ * expanded array, then the implementation is allowed to modify that object
+ * in-place and return the same object.)
* ----------------
*/
typedef struct ArrayRef
Oid refelemtype; /* type of the array elements */
int32 reftypmod; /* typmod of the array (and elements too) */
Oid refcollid; /* OID of collation, or InvalidOid if none */
- List *refupperindexpr;/* expressions that evaluate to upper array
- * indexes */
- List *reflowerindexpr;/* expressions that evaluate to lower array
- * indexes */
+ List *refupperindexpr; /* expressions that evaluate to upper
+ * array indexes */
+ List *reflowerindexpr; /* expressions that evaluate to lower
+ * array indexes, or NIL for single array
+ * element */
Expr *refexpr; /* the expression that evaluates to an array
* value */
Expr *refassgnexpr; /* expression for the source value, or NULL if
* NB: equal() ignores CoercionForm fields, therefore this *must* not carry
* any semantically significant information. We need that behavior so that
* the planner will consider equivalent implicit and explicit casts to be
- * equivalent. In cases where those actually behave differently, the coercion
+ * equivalent. In cases where those actually behave differently, the coercion
* function's arguments will be different.
*/
typedef enum CoercionForm
Oid funcid; /* PG_PROC OID of the function */
Oid funcresulttype; /* PG_TYPE OID of result value */
bool funcretset; /* true if function returns set */
- bool funcvariadic; /* true if VARIADIC was used in call */
+ bool funcvariadic; /* true if variadic arguments have been
+ * combined into an array last argument */
CoercionForm funcformat; /* how to display this function call */
Oid funccollid; /* OID of collation of result */
Oid inputcollid; /* OID of collation that function should use */
* BoolExpr - expression node for the basic Boolean operators AND, OR, NOT
*
* Notice the arguments are given as a List. For NOT, of course the list
- * must always have exactly one element. For AND and OR, the executor can
- * handle any number of arguments. The parser generally treats AND and OR
- * as binary and so it typically only produces two-element lists, but the
- * optimizer will flatten trees of AND and OR nodes to produce longer lists
- * when possible. There are also a few special cases where more arguments
- * can appear before optimization.
+ * must always have exactly one element. For AND and OR, there can be two
+ * or more arguments.
*/
typedef enum BoolExprType
{
* SubLink
*
* A SubLink represents a subselect appearing in an expression, and in some
- * cases also the combining operator(s) just above it. The subLinkType
+ * cases also the combining operator(s) just above it. The subLinkType
* indicates the form of the expression represented:
* EXISTS_SUBLINK EXISTS(SELECT ...)
* ALL_SUBLINK (lefthand) op ALL (SELECT ...)
* ANY_SUBLINK (lefthand) op ANY (SELECT ...)
* ROWCOMPARE_SUBLINK (lefthand) op (SELECT ...)
* EXPR_SUBLINK (SELECT with single targetlist item ...)
+ * MULTIEXPR_SUBLINK (SELECT with multiple targetlist items ...)
* ARRAY_SUBLINK ARRAY(SELECT with single targetlist item ...)
* CTE_SUBLINK WITH query (never actually part of an expression)
* For ALL, ANY, and ROWCOMPARE, the lefthand is a list of expressions of the
* same length as the subselect's targetlist. ROWCOMPARE will *always* have
* a list with more than one entry; if the subselect has just one target
* then the parser will create an EXPR_SUBLINK instead (and any operator
- * above the subselect will be represented separately). Note that both
- * ROWCOMPARE and EXPR require the subselect to deliver only one row.
+ * above the subselect will be represented separately).
+ * ROWCOMPARE, EXPR, and MULTIEXPR require the subselect to deliver at most
+ * one row (if it returns no rows, the result is NULL).
* ALL, ANY, and ROWCOMPARE require the combining operators to deliver boolean
* results. ALL and ANY combine the per-row results using AND and OR
* semantics respectively.
*
* NOTE: in the raw output of gram.y, testexpr contains just the raw form
* of the lefthand expression (if any), and operName is the String name of
- * the combining operator. Also, subselect is a raw parsetree. During parse
+ * the combining operator. Also, subselect is a raw parsetree. During parse
* analysis, the parser transforms testexpr into a complete boolean expression
* that compares the lefthand value(s) to PARAM_SUBLINK nodes representing the
* output columns of the subselect. And subselect is transformed to a Query.
* This is the representation seen in saved rules and in the rewriter.
*
- * In EXISTS, EXPR, and ARRAY SubLinks, testexpr and operName are unused and
- * are always null.
+ * In EXISTS, EXPR, MULTIEXPR, and ARRAY SubLinks, testexpr and operName
+ * are unused and are always null.
+ *
+ * subLinkId is currently used only for MULTIEXPR SubLinks, and is zero in
+ * other SubLinks. This number identifies different multiple-assignment
+ * subqueries within an UPDATE statement's SET list. It is unique only
+ * within a particular targetlist. The output column(s) of the MULTIEXPR
+ * are referenced by PARAM_MULTIEXPR Params appearing elsewhere in the tlist.
*
* The CTE_SUBLINK case never occurs in actual SubLink nodes, but it is used
* in SubPlans generated for WITH subqueries.
ANY_SUBLINK,
ROWCOMPARE_SUBLINK,
EXPR_SUBLINK,
+ MULTIEXPR_SUBLINK,
ARRAY_SUBLINK,
CTE_SUBLINK /* for SubPlans only */
} SubLinkType;
{
Expr xpr;
SubLinkType subLinkType; /* see above */
+ int subLinkId; /* ID (1..n); 0 if not MULTIEXPR */
Node *testexpr; /* outer-query test for ALL/ANY/ROWCOMPARE */
List *operName; /* originally specified operator name */
- Node *subselect; /* subselect as Query* or parsetree */
+ Node *subselect; /* subselect as Query* or raw parsetree */
int location; /* token location, or -1 if unknown */
} SubLink;
* list). In this case testexpr is NULL to avoid duplication.
*
* The planner also derives lists of the values that need to be passed into
- * and out of the subplan. Input values are represented as a list "args" of
+ * and out of the subplan. Input values are represented as a list "args" of
* expressions to be evaluated in the outer-query context (currently these
* args are always just Vars, but in principle they could be any expression).
* The values are assigned to the global PARAM_EXEC params indexed by parParam
/* Extra data useful for determining subplan's output type: */
Oid firstColType; /* Type of first column of subplan result */
int32 firstColTypmod; /* Typmod of first column of subplan result */
- Oid firstColCollation; /* Collation of first column of
- * subplan result */
+ Oid firstColCollation; /* Collation of first column of subplan
+ * result */
/* Information about execution strategy: */
bool useHashTable; /* TRUE to store subselect output in a hash
* table (implies we are doing "IN") */
bool unknownEqFalse; /* TRUE if it's okay to return FALSE when the
* spec result is UNKNOWN; this allows much
* simpler handling of null values */
+ bool parallel_safe; /* is the subplan parallel-safe? */
+ /* Note: parallel_safe does not consider contents of testexpr or args */
/* Information for passing params into and out of the subselect: */
/* setParam and parParam are lists of integers (param IDs) */
List *setParam; /* initplan subqueries have to set these
* the assign case of ArrayRef, this is used to implement UPDATE of a
* portion of a column.
*
+ * resulttype is always a named composite type (not a domain). To update
+ * a composite domain value, apply CoerceToDomain to the FieldStore.
+ *
* A single FieldStore can actually represent updates of several different
- * fields. The parser only generates FieldStores with single-element lists,
+ * fields. The parser only generates FieldStores with single-element lists,
* but the planner will collapse multiple updates of the same base column
* into one FieldStore.
* ----------------
* ArrayCoerceExpr
*
* ArrayCoerceExpr represents a type coercion from one array type to another,
- * which is implemented by applying the indicated element-type coercion
- * function to each element of the source array. If elemfuncid is InvalidOid
- * then the element types are binary-compatible, but the coercion still
- * requires some effort (we have to fix the element type ID stored in the
- * array header).
+ * which is implemented by applying the per-element coercion expression
+ * "elemexpr" to each element of the source array. Within elemexpr, the
+ * source element is represented by a CaseTestExpr node. Note that even if
+ * elemexpr is a no-op (that is, just CaseTestExpr + RelabelType), the
+ * coercion still requires some effort: we have to fix the element type OID
+ * stored in the array header.
* ----------------
*/
{
Expr xpr;
Expr *arg; /* input expression (yields an array) */
- Oid elemfuncid; /* OID of element coercion function, or 0 */
+ Expr *elemexpr; /* expression representing per-element work */
Oid resulttype; /* output type of coercion (an array type) */
int32 resulttypmod; /* output typmod (also element typmod) */
Oid resultcollid; /* OID of collation, or InvalidOid if none */
- bool isExplicit; /* conversion semantics flag to pass to func */
CoercionForm coerceformat; /* how to display this node */
int location; /* token location, or -1 if unknown */
} ArrayCoerceExpr;
* needed for the destination type plus possibly others; the columns need not
* be in the same positions, but are matched up by name. This is primarily
* used to convert a whole-row value of an inheritance child table into a
- * valid whole-row value of its parent table's rowtype.
+ * valid whole-row value of its parent table's rowtype. Both resulttype
+ * and the exposed type of "arg" must be named composite types (not domains).
* ----------------
*/
* and the testexpr in the second case.
*
* In the raw grammar output for the second form, the condition expressions
- * of the WHEN clauses are just the comparison values. Parse analysis
+ * of the WHEN clauses are just the comparison values. Parse analysis
* converts these to valid boolean expressions of the form
* CaseTestExpr '=' compexpr
* where the CaseTestExpr node is a placeholder that emits the correct
*
* Note: the list of fields must have a one-for-one correspondence with
* physical fields of the associated rowtype, although it is okay for it
- * to be shorter than the rowtype. That is, the N'th list element must
+ * to be shorter than the rowtype. That is, the N'th list element must
* match up with the N'th physical field. When the N'th physical field
* is a dropped column (attisdropped) then the N'th list element can just
- * be a NULL constant. (This case can only occur for named composite types,
+ * be a NULL constant. (This case can only occur for named composite types,
* not RECORD types, since those are built from the RowExpr itself rather
* than vice versa.) It is important not to assume that length(args) is
* the same as the number of columns logically present in the rowtype.
*
* colnames provides field names in cases where the names can't easily be
- * obtained otherwise. Names *must* be provided if row_typeid is RECORDOID.
+ * obtained otherwise. Names *must* be provided if row_typeid is RECORDOID.
* If row_typeid identifies a known composite type, colnames can be NIL to
* indicate the type's cataloged field names apply. Note that colnames can
* be non-NIL even for a composite type, and typically is when the RowExpr
* was created by expanding a whole-row Var. This is so that we can retain
* the column alias names of the RTE that the Var referenced (which would
- * otherwise be very difficult to extract from the parsetree). Like the
+ * otherwise be very difficult to extract from the parsetree). Like the
* args list, colnames is one-for-one with physical fields of the rowtype.
*/
typedef struct RowExpr
Oid row_typeid; /* RECORDOID or a composite type's ID */
/*
+ * row_typeid cannot be a domain over composite, only plain composite. To
+ * create a composite domain value, apply CoerceToDomain to the RowExpr.
+ *
* Note: we deliberately do NOT store a typmod. Although a typmod will be
* associated with specific RECORD types at runtime, it will differ for
* different backends, and so cannot safely be stored in stored
- * parsetrees. We must assume typmod -1 for a RowExpr node.
+ * parsetrees. We must assume typmod -1 for a RowExpr node.
*
* We don't need to store a collation either. The result type is
* necessarily composite, and composite types never have a collation.
int location; /* token location, or -1 if unknown */
} MinMaxExpr;
+/*
+ * SQLValueFunction - parameterless functions with special grammar productions
+ *
+ * The SQL standard categorizes some of these as <datetime value function>
+ * and others as <general value specification>. We call 'em SQLValueFunctions
+ * for lack of a better term. We store type and typmod of the result so that
+ * some code doesn't need to know each function individually, and because
+ * we would need to store typmod anyway for some of the datetime functions.
+ * Note that currently, all variants return non-collating datatypes, so we do
+ * not need a collation field; also, all these functions are stable.
+ */
+typedef enum SQLValueFunctionOp
+{
+ SVFOP_CURRENT_DATE,
+ SVFOP_CURRENT_TIME,
+ SVFOP_CURRENT_TIME_N,
+ SVFOP_CURRENT_TIMESTAMP,
+ SVFOP_CURRENT_TIMESTAMP_N,
+ SVFOP_LOCALTIME,
+ SVFOP_LOCALTIME_N,
+ SVFOP_LOCALTIMESTAMP,
+ SVFOP_LOCALTIMESTAMP_N,
+ SVFOP_CURRENT_ROLE,
+ SVFOP_CURRENT_USER,
+ SVFOP_USER,
+ SVFOP_SESSION_USER,
+ SVFOP_CURRENT_CATALOG,
+ SVFOP_CURRENT_SCHEMA
+} SQLValueFunctionOp;
+
+typedef struct SQLValueFunction
+{
+ Expr xpr;
+ SQLValueFunctionOp op; /* which function this is */
+ Oid type; /* result type/typmod */
+ int32 typmod;
+ int location; /* token location, or -1 if unknown */
+} SQLValueFunction;
+
/*
* XmlExpr - various SQL/XML functions requiring special grammar productions
*
* 'args' carries all other arguments.
*
* Note: result type/typmod/collation are not stored, but can be deduced
- * from the XmlExprOp. The type/typmod fields are just used for display
+ * from the XmlExprOp. The type/typmod fields are just used for display
* purposes, and are NOT necessarily the true result type of the node.
- * (We also use type == InvalidOid to mark a not-yet-parse-analyzed XmlExpr.)
*/
typedef enum XmlExprOp
{
* NullTest represents the operation of testing a value for NULLness.
* The appropriate test is performed and returned as a boolean Datum.
*
- * NOTE: the semantics of this for rowtype inputs are noticeably different
- * from the scalar case. We provide an "argisrow" flag to reflect that.
+ * When argisrow is false, this simply represents a test for the null value.
+ *
+ * When argisrow is true, the input expression must yield a rowtype, and
+ * the node implements "row IS [NOT] NULL" per the SQL standard. This
+ * includes checking individual fields for NULLness when the row datum
+ * itself isn't NULL.
+ *
+ * NOTE: the combination of a rowtype input and argisrow==false does NOT
+ * correspond to the SQL notation "row IS [NOT] NULL"; instead, this case
+ * represents the SQL notation "row IS [NOT] DISTINCT FROM NULL".
* ----------------
*/
Expr xpr;
Expr *arg; /* input expression */
NullTestType nulltesttype; /* IS NULL, IS NOT NULL */
- bool argisrow; /* T if input is of a composite type */
+ bool argisrow; /* T to perform field-by-field null checks */
+ int location; /* token location, or -1 if unknown */
} NullTest;
/*
Expr xpr;
Expr *arg; /* input expression */
BoolTestType booltesttype; /* test type */
+ int location; /* token location, or -1 if unknown */
} BooleanTest;
/*
*
* CoerceToDomain represents the operation of coercing a value to a domain
* type. At runtime (and not before) the precise set of constraints to be
- * checked will be determined. If the value passes, it is returned as the
- * result; if not, an error is raised. Note that this is equivalent to
+ * checked will be determined. If the value passes, it is returned as the
+ * result; if not, an error is raised. Note that this is equivalent to
* RelabelType in the scenario where no constraints are applied.
*/
typedef struct CoerceToDomain
/*
* Placeholder node for the value to be processed by a domain's check
- * constraint. This is effectively like a Param, but can be implemented more
+ * constraint. This is effectively like a Param, but can be implemented more
* simply since we need only one replacement value at a time.
*
* Note: the typeId/typeMod/collation will be set from the domain's base type,
* Placeholder node for a DEFAULT marker in an INSERT or UPDATE command.
*
* This is not an executable expression: it must be replaced by the actual
- * column default expression during rewriting. But it is convenient to
+ * column default expression during rewriting. But it is convenient to
* treat it as an expression node during parsing and rewriting.
*/
typedef struct SetToDefault
int cursor_param; /* refcursor parameter number, or 0 */
} CurrentOfExpr;
+/*
+ * NextValueExpr - get next value from sequence
+ *
+ * This has the same effect as calling the nextval() function, but it does not
+ * check permissions on the sequence. This is used for identity columns,
+ * where the sequence is an implicit dependency without its own permissions.
+ */
+typedef struct NextValueExpr
+{
+ Expr xpr;
+ Oid seqid;
+ Oid typeId;
+} NextValueExpr;
+
+/*
+ * InferenceElem - an element of a unique index inference specification
+ *
+ * This mostly matches the structure of IndexElems, but having a dedicated
+ * primnode allows for a clean separation between the use of index parameters
+ * by utility commands, and this node.
+ */
+typedef struct InferenceElem
+{
+ Expr xpr;
+ Node *expr; /* expression to infer from, or NULL */
+ Oid infercollid; /* OID of collation, or InvalidOid */
+ Oid inferopclass; /* OID of att opclass, or InvalidOid */
+} InferenceElem;
+
/*--------------------
* TargetEntry -
* a target entry (used in query target lists)
* single expression tree.
*
* In a SELECT's targetlist, resno should always be equal to the item's
- * ordinal position (counting from 1). However, in an INSERT or UPDATE
+ * ordinal position (counting from 1). However, in an INSERT or UPDATE
* targetlist, resno represents the attribute number of the destination
* column for the item; so there may be missing or out-of-order resnos.
* It is even legal to have duplicated resnos; consider
* UPDATE table SET arraycol[1] = ..., arraycol[2] = ..., ...
* The two meanings come together in the executor, because the planner
* transforms INSERT/UPDATE tlists into a normalized form with exactly
- * one entry for each column of the destination table. Before that's
+ * one entry for each column of the destination table. Before that's
* happened, however, it is risky to assume that resno == position.
* Generally get_tle_by_resno() should be used rather than list_nth()
* to fetch tlist entries by resno, and only in SELECT should you assume
* resname is required to represent the correct column name in non-resjunk
* entries of top-level SELECT targetlists, since it will be used as the
* column title sent to the frontend. In most other contexts it is only
- * a debugging aid, and may be wrong or even NULL. (In particular, it may
+ * a debugging aid, and may be wrong or even NULL. (In particular, it may
* be wrong in a tlist from a stored rule, if the referenced column has been
- * renamed by ALTER TABLE since the rule was made. Also, the planner tends
+ * renamed by ALTER TABLE since the rule was made. Also, the planner tends
* to store NULL rather than look up a valid name for tlist entries in
* non-toplevel plan nodes.) In resjunk entries, resname should be either
* a specific system-generated name (such as "ctid") or NULL; anything else
* risks confusing ExecGetJunkAttribute!
*
* ressortgroupref is used in the representation of ORDER BY, GROUP BY, and
- * DISTINCT items. Targetlist entries with ressortgroupref=0 are not
+ * DISTINCT items. Targetlist entries with ressortgroupref=0 are not
* sort/group items. If ressortgroupref>0, then this item is an ORDER BY,
- * GROUP BY, and/or DISTINCT target value. No two entries in a targetlist
+ * GROUP BY, and/or DISTINCT target value. No two entries in a targetlist
* may have the same nonzero ressortgroupref --- but there is no particular
* meaning to the nonzero values, except as tags. (For example, one must
* not assume that lower ressortgroupref means a more significant sort key.)
* The order of the associated SortGroupClause lists determine the semantics.
*
* resorigtbl/resorigcol identify the source of the column, if it is a
- * simple reference to a column of a base table (or view). If it is not
+ * simple reference to a column of a base table (or view). If it is not
* a simple reference, these fields are zeroes.
*
* If resjunk is true then the column is a working column (such as a sort key)
Expr *expr; /* expression to evaluate */
AttrNumber resno; /* attribute number (see notes above) */
char *resname; /* name of the column (could be NULL) */
- Index ressortgroupref;/* nonzero if referenced by a sort/group
- * clause */
+ Index ressortgroupref; /* nonzero if referenced by a sort/group
+ * clause */
Oid resorigtbl; /* OID of column's source table */
AttrNumber resorigcol; /* column's number in source table */
bool resjunk; /* set to true to eliminate the attribute from
*
* NOTE: the qualification expressions present in JoinExpr nodes are
* *in addition to* the query's main WHERE clause, which appears as the
- * qual of the top-level FromExpr. The reason for associating quals with
+ * qual of the top-level FromExpr. The reason for associating quals with
* specific nodes in the jointree is that the position of a qual is critical
* when outer joins are present. (If we enforce a qual too soon or too late,
* that may cause the outer join to produce the wrong set of NULL-extended
* If he writes NATURAL then parse analysis generates the equivalent USING()
* list, and from that fills in "quals" with the right equality comparisons.
* If he writes USING() then "quals" is filled with equality comparisons.
- * If he writes ON() then only "quals" is set. Note that NATURAL/USING
+ * If he writes ON() then only "quals" is set. Note that NATURAL/USING
* are not equivalent to ON() since they also affect the output column list.
*
* alias is an Alias node representing the AS alias-clause attached to the
* restricts visibility of the tables/columns inside it.
*
* During parse analysis, an RTE is created for the Join, and its index
- * is filled into rtindex. This RTE is present mainly so that Vars can
+ * is filled into rtindex. This RTE is present mainly so that Vars can
* be created that refer to the outputs of the join. The planner sometimes
* generates JoinExprs internally; these can have rtindex = 0 if there are
* no join alias variables referencing such joins.
Node *quals; /* qualifiers on join, if any */
} FromExpr;
-#endif /* PRIMNODES_H */
+/*----------
+ * OnConflictExpr - represents an ON CONFLICT DO ... expression
+ *
+ * The optimizer requires a list of inference elements, and optionally a WHERE
+ * clause to infer a unique index. The unique index (or, occasionally,
+ * indexes) inferred are used to arbitrate whether or not the alternative ON
+ * CONFLICT path is taken.
+ *----------
+ */
+typedef struct OnConflictExpr
+{
+ NodeTag type;
+ OnConflictAction action; /* DO NOTHING or UPDATE? */
+
+ /* Arbiter */
+ List *arbiterElems; /* unique index arbiter list (of
+ * InferenceElem's) */
+ Node *arbiterWhere; /* unique index arbiter WHERE clause */
+ Oid constraint; /* pg_constraint OID for arbiter */
+
+ /* ON CONFLICT UPDATE */
+ List *onConflictSet; /* List of ON CONFLICT SET TargetEntrys */
+ Node *onConflictWhere; /* qualifiers to restrict UPDATE to */
+ int exclRelIndex; /* RT index of 'excluded' relation */
+ List *exclRelTlist; /* tlist of the EXCLUDED pseudo relation */
+} OnConflictExpr;
+
+#endif /* PRIMNODES_H */